1. Field of the Invention
The present invention relates to fluid pump assemblies in general, and more particularly, to positive displacement fluid pump assemblies.
2. Description of the Prior Art
In conventional integrated pressurized fluid systems the fluid pressure is normally generated by positive displacement pumps, such as gerotor pumps, gear pumps, etc. The gerotor hydraulic pumps are becoming more and more commonplace. The gerotor pumps could be found in many industrial applications such as motor vehicles, robots and mechanized transportation equipment. The hydraulic gerotor pumps are generally preferred in applications associated with vehicular torque couplings, including limited slip differentials. Gerotor pumps are sometimes built into the differential mechanism and housed within the differential case housing. With these increasing numbers of applications comes an ever increasing need for application specific designs, designs including disengageable drives. As gerotor pumps are high torque devices, disengageable drives mean expensive clutches and/or restrictions for engagement. Present attempts to remedy these characteristics, such as multi-pack clutches, external recirculation valves or one-way drive mechanisms, are not efficient in either cost or practicality.
Therefore, the need exists to overcome these shortcomings of the prior art by providing a more efficient and cost-effective selectively operated positive displacement fluid pump assembly.